In the use of a drive assembly, it is desirable to take planetary gear reduction substantially within a tandem housing connected to said drive assembly. The invention relates to a first bearing element positioned between and in contact with a driven member or sprocket and a first housing element of the drive assembly to support the driven member in rotatable relationship relative to the first housing element. A second bearing element is positioned between a ring gear element of a planetary gear assembly and the first housing element and in contact with said first housing element. Said second bearing element supports the first housing element in rotatable relationship relative to the gear assembly.
U.S. Pat. No. 3,452,612 which issued on July 1, 1969, to Casey, discloses a drive assembly having a planetary gear assembly for gear reduction in the driving of a wheel assembly. A first bearing element is positioned between the driven member or wheel assembly and the axle housing.
U.S. Pat. No. 3,454,109 which issued on July 8, 1969, to Roberts, discloses a pivotal tandem housing of a motor grader. Gear reduction is taken by chain driven sprockets mounted inside the tandem housing.
A work vehicle, for example, commonly has a planetary final drive connected to the ends of each axle housing. Gear reduction is taken by a planetary gear assembly in the final drive. The axle shaft provides input through rotation of a sun gear. The resultant action of the planet gears relative to the ring gear provides an output through the planet carrier. The carrier typically drives a wheel assembly.
It is desirable to pivotally connect a tandem housing to the work vehicle in order to mount tandem wheels to the final drive of the vehicle. This provides low ground pressure, increased tractive effort and better response to changing terrain on such vehicles as motor graders and log skidders. A sprocket, positioned in the tandem housing, is driven by the planet carrier. A chain engaging the sprocket drives the wheels.
However, connecting the tandem housing to the ring gear in order to position the planetary gear assembly inside the tandem housing tends to cause an overturning reaction force in the housing. The result is uneven wheel loading and possible rotation of the tandem housing during vehicle operation.
Therefore, in the drive assembly, it is desirable to position a first bearing element between and in contact with the driven member or sprocket and a housing element and a second bearing element between the ring gear and housing elements and in contact with the housing element. The tandem housing is therefore connectable to the housing element in a manner substantially enclosing the drive assembly for gear reduction inside said housing.